a: =3x(y-2)-5(y-2)
=(y-2)(3x-5)
b: =(2x-5y)(2x+5y)
c: =x(x^3-8)
=x(x-2)(x^2+2x+4)
a)
\(3x\left(y-2\right)+5\left(2-y\right)\\=3x\left(y-2\right)-5\left(y-2\right)\\ =\left(y-2\right)\left(3x-5\right) \)
b)
\(4x^2-25y^2\\ =\left(2x-5y\right)\left(2x+5y\right)\)
c)
\(x^4-8x\\ =x\left(x^3-8\right)\\ =x\left(x-2\right)\left(x^2+2x+4\right)\)
\(a,3x\left(y-2\right)+5\left(2-y\right)=3x\left(y-2\right)-5\left(y-2\right)=\left(y-2\right)\left(3x-5\right)\)
\(b,4x^2-25y^2=\left(2x-5y\right)\left(2x+5y\right)\)
\(c,x^4-8x=x\left(x^3-8\right)=x\left(x-2\right)\left(x^2+4x+4\right)\)